Unable to decrypt aes ciphertext with slowaes (javascript)
I have a cipher text I encoded with the AesManaged .Net classes.
plaintext: "string"
password: "password"
this is the c# code I use to encrypt:
private AesManaged AESCipher;
private String Password;
public AES(String Password)
{
this.AESCipher = new AesManaged();
this.AESCipher.Mode = CipherMode.CBC;
this.AESCipher.Padding = PaddingMode.PKCS7;
this.AESCipher.IV = HexStringToByteArray("000102030405060708090A0B0C0D0E0F");
this.AESCipher.KeySize = 256;
this.AESCipher.BlockSize = 128;
this.Iterations = 1000;
this.Salt = System.Text.Encoding.ASCII.GetBytes("saltsalt");
this.Password = Password;
}
public String Encrypt(String PlainText)
{
this.AESCipher.Key = GenerateKey();
byte[] plainTextBytes = System.Text.Encoding.ASCII.GetBytes(PlainText);
ICryptoTransform transform = this.AESCipher.CreateEncryptor();
return Convert.ToBase64String(transform.TransformFinalBlock(plainTextBytes, 0, plainTextBytes.Length));
}
public String Decrypt(String CipherText)
{
this.AESCipher.Key = GenerateKey();
byte[] cipherTextBytes = Convert.FromBase64String(CipherText);
ICryptoTransform transform = this.AESCipher.CreateDecryptor();
return System.Text.Encoding.ASCII.GetString(transform.TransformFinalBlock(cipherTextBytes, 0, cipherTextBytes.Length));
}
private static string ByteArrayToHexString(byte[] b)
{
System.Text.StringBuilder sb1 = ne开发者_如何转开发w System.Text.StringBuilder();
int i = 0;
for (i = 0; i < b.Length; i++)
{
sb1.Append(System.String.Format("{0:X2}", b[i]));
}
return sb1.ToString().ToUpper();
}
private static byte[] HexStringToByteArray(string s)
{
var r = new byte[s.Length / 2];
for (int i = 0; i < s.Length; i += 2)
{
r[i / 2] = (byte)Convert.ToInt32(s.Substring(i, 2), 16);
}
return r;
}
private byte[] GenerateKey()
{
var rfc2898 = new System.Security.Cryptography.Rfc2898DeriveBytes(this.Password, this.Salt, this.Iterations);
return rfc2898.GetBytes(this.KeySizeInBits/8);
}
When I decrypt with slowAES and pbkdf2 the decrypted string is not correct.
The cipher text (base64) is : "MJ8gxKkUKU/S+CgLPf8Sjg=="
the decrypted text returned is: "supkj`"
My JavaScript is:
function asciiToByteArray(s)
{
var r= Array(s.length);
for (var i = 0; i < s.length; i++)
{
r[i]= s.charCodeAt(i);
}
return r;
}
function byteArrayToAscii(a) {
var r = "";
for (var i = 0; i < a.length; i++) {
r += String.fromCharCode(a[i]);
}
return r;
}
function hexStringToByteArray(s) {
try { hexcase } catch (e) { hexcase = 0; }
var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
var r = Array(s.length / 2);
for (var i = 0; i < s.length; i += 2) {
r[i / 2] = parseInt(s.substr(i, 2), 16);
}
return r;
}
function byteArrayToHexString(a) {
try { hexcase } catch (e) { hexcase = 0; }
var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
var r = "";
for (var i = 0; i < a.length; i++) {
var b = hex_tab.charAt((a[i] >> 4) & 0x0F) +
hex_tab.charAt(a[i] & 0x0F);
r += b;
}
return r;
}
var mypbkdf2 = new PBKDF2("password", "saltsalt", 1000, 32);
var newKey;
var status_callback = function(percent_done) {
document.getElementById("status").innerHTML = "Computed " + percent_done + "%"
};
var result_callback = function(key) {
document.getElementById("status").innerHTML = "The derived key is: " + key
newKey = key;
var bytes = cryptoHelpers.base64.decode(document.getElementById("string").innerHTML);
var result = slowAES.decrypt(bytes, 6, slowAES.modeOfOperation.CBC, hexStringToByteArray(key), 32, "000102030405060708090A0B0C0D0E0F")
alert(byteArrayToAscii(result));
};
mypbkdf2.deriveKey(status_callback, result_callback);
Can anyone see what I'm doing wrong?
Many Thanks
Ok do I get points for answering my own question?
I spotted that in the JavaScript I was passing the IV as a HEX string instead of a char array.
var result = slowAES.decrypt(bytes, 6, slowAES.modeOfOperation.CBC, hexStringToByteArray(key), 32, "000102030405060708090A0B0C0D0E0F")
should be
var result = slowAES.decrypt(bytes, 6, slowAES.modeOfOperation.CBC, hexStringToByteArray(key), 32, hexStringToByteArray("000102030405060708090A0B0C0D0E0F"))
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